Trigger switch for motor vehicle safety devices

ABSTRACT

A trigger switch mechanism for motor vehicle safety devices which senses deceleration of a given magnitude resulting from a collision of the motor vehicle in order to actuate the safety devices. The mechanism comprises an upright cylinder within which an electrically conductive rockable weight is normally kept aligned with respect to the surrounding cylinder in a depending manner by a rodlike spring and a coiled spring. An arcuate contact is provided on the inner wall of the upright cylinder in front of the rockable weight at a suitable space therefrom. An arcuate damper is also provided on the inner wall of the upright cylinder opposite to the arcuate contact in such a manner as to partially surround the rockable weight thereby serving to absorb the usual shocks and vibrations of the rockable weight developed during operation of the vehicle. In operation, if the trigger switch mechanism is subjected to deceleration of a given magnitude resulting from a collision, then the rockable weight swings and strikes against the arcuate contact, thereby establishing an electrical connection therebetween.

United States Patent Haruna et al.

TRIGGER SWITCH FOR MOTOR VEHICLE SAFETY DEVICES Takashi Haruna,Yokosuka; Akira Shimano, Yokohama; both of Japan Nissan Motor Yokohama,Japan Filed: Feb. 19,1971

Appl.No.:' 116,962

[72] Inventors:

[73] Assignee: Company,

[30] Foreign Application Priority Data Mar. 18, 1970 Japan ..45/26023US. Cl. ..200/6l.48, 280/150 AB ..I-I0lh-35/l4 [56] References CitedUNITED STATES PATENTS I 7? i 9: a: I

Limited, 7 v

Field of Search ..200/6l.45t51.53;v

Primary Examiner-Robert K'. Schaefer Assistant Examiner-M. GinsburgAttorney-John Lezdey [57] ABSTRACT I a collision of the motor vehicle inorder to actuate the safety devices. The mechanism comprises an uprightcylinder within which an electrically conductive rockable weight isnormally kept aligned with respect to the surrounding cylinder in adepending manner by a rodlike spring and a coiled spring. An arcuatecontact is provided on the inner wall of the upright cylinder in frontof the rockable weight at a suitable space therefrom. An arcuate damperis also provided on the inner wall of the upright cylinder opposite tothe arcuate contact in such a manner as to partially surround therockable weight thereby serving to absorb the usual shocks andvibrations of the rockable weight developed during operation of thevehicle. In operation, if the trigger switch mechanism is subjected todeceleration of a given magnitude resulting from a collision, then therockable weight swings and strikes against the arcuate contact, therebyestablishing an electrical connection therebetween.

I 9 Claims, 2 Drawing Figures PATENT 150m mm v 3.639710 )Y I I e a z 4 ri INVENTORS TAKASHI HARHNA AKIRA SHIMANO TTORNEY TRIGGER SWITCH FORMOTOR VEHICLE SAFE DEVICES This invention relates to motor vehiclesafety devices and more particularly to a trigger switch mechanism forsensing deceleration of a given magnitude resulting from a collision ofthe motor vehicle to actuate the safety devices.

Various motor vehicle safety devices have heretofore been proposed anddemonstrated, including one having a netting or an air bag which isautomatically positioned in a protective position in the event of acollision, thereby avoiding whiplash injuries of the vehicle occupants.These devices, usually, employ explosives to initiate the netting or airbag into action. However, the use, of such hazardous initiatorssometimes jeopardized the installation of the safety device of this typebecause of restrictions from local automotive regulations that prohibitthe storage of hazardous materials in motor vehicles.

It is therefore an object of this invention to provide a new andimproved trigger switch mechanism that is capable of sensingdeceleration of a given magnitude resulting from a collision so as toactuate a motor vehicle safety device without use of any hazardousmaterial such as chemical explosives.

It is another object of this invention to provide a quick respondingtrigger switch mechanism for a motor vehicle safety device.

It is a further object of this invention to provide a trigger switchmechanism which is simple in construction and has an increasedreliability.

In the drawings:

FIG. 1 is a longitudinal section of a trigger switch mechanism embodyingthis invention; and

FIG. 2 is a cross section taken along the line IIII of FIG. 1, showingthe relationship in position between a rockable weight and two arcuatemembers used in the trigger switch mechanism.

Referring to FIG. 1, there is shown an example of a trigger switchmechanism according to this invention, which forms part of a motorvehicle safety device having a netting or an air bag (not shown). Asshown, the switch mechanism comprises a base member on which anelectrically nonconductive cylinder 11 is fixedly mounted in an uprightmanner as by a screw 12. An electrically conductive plate 13 is mountedatop the cylindrical member 11 as by screws 14 and 15. A rodlike spring16 is anchored at its uppermost end to the plate 13 and dependstherefrom. The rodlike spring 16 carries at its lowermost end a rockableweight 17 which is of generally cylindrical construction, as is shown inFIG. 2. The rockable weight 17 has a recessed control portion 18 formedin its lower end surface.

A ball 19 is forced against the recessed control portion 18 by a coiledspring 20 to maintain the alignment of the weight 17 relative to thesurrounding cylinder 11. The coiled spring 20 is mounted in acylindrical recess 21 formed in the center of the base member 10. Theforce of compression of the coiled spring 20 can be adjusted by anadjustment screw 22 provided at the bottom of the base member 10.

An arcuate member 23 which acts as an electrical contact is secured tothe inner wall of the cylindrical member 1 l in front of the rockableweight 17 at a suitable space therefrom. Preferably, the arcuate member23 is positioned concentrically with respect to the rockable weight 17,as is shown in FIG. 2. The angle a which the arcuate member 23 formswith respect to the center 24 of the rockable weight 17 depends upon theazimuth angle through which detection of mechanical shocks resultingfrom a collision is desired.

Another arcuate member 25 is secured to the inner wall of thecylindrical member 11 opposite to the arcuate member 23 in such a manneras to partially surround the rockable weight 17, as is shown in FIG. 2.In a preferred embodiment, the arcuate member 25 is made of electricallynonconductive material and acts as a damper which absorbs the usualshocks or vibrations of the rockable weight 17 developed or arisingduring operation of the vehicle.

The plate 13, rodlike spring 16, rockable weight 17 and arcuate member23 are all made of electrically conductive material. Connections to acontrol circuit for actuating a motor vehicle safety device (not shown)are made by leads 26 and 27 which are electrically connected to theplate 13 and the arcuate member 23, respectively.

It is to be noted that the force of compression of the coiled spring 20is so adjusted that if the switch mechanism thus constructed issubjected to deceleration in the direction of arrow 28 and of a givenmagnitude, then rockable weight 17 swings and strikes against thearcuate member 23.

In operation, when the trigger switch mechanism issubjected tomechanical shocks of a given magnitude, for example, due to a collision,the rockable weight 17 is forced forwardly against the actions of therodlike springs 16 and coiled springs 20, coming into contact with thearcuate member 23 whereby a circuit connection between the leads 26 and27 is established.

As has been described above, this invention provides a new and improvedtrigger switch mechanism for motor vehicle safety devices which iscapable of sensing deceleration of a given magnitude resulting from acollision with increased reliability so as to actuate the safety deviceswithout use of any hazardous materials such as chemical explosives.

What is claimed is:

l. A trigger switch mechanism for sensing deceleration of a givenmagnitude resulting from a collision of the motor vehicle to actuatesafety devices mounted thereon, said mechanism comprising: a basemember, a cylindrical member mounted on said base member in an uprightmanner, a plate member mounted atop said cylindrical member, a rodlikespring anchored at its uppermost end to said plate member, anelectrically conductive rockable weight carried by said rodlike springand having a recessed control portion formed in its lower end surface, aball member held in said recessed control portion by a regulated springaction, a coiled spring holding said ball member in said recessedcontrol portion, a contact member provided on the inner wall of saidcylindrical member in front of said rockable weight at a suitable spacetherefrom, and a clamping member provided on the inner wall of saidcylindrical member opposite to said contact member for partiallysurrounding said rockable weight thereby serving to absorb the usualshocks and vibrations of said rockable weight developed during operationof the motor vehicle, said rockable weight being forced forwardly cominginto contact with said contact member when said trigger switch mechanismis subjected to said deceleration.

2. A trigger switch mechanism according to claim I, in which saidcylindrical member is made of electrically nonconductive material.

3. A trigger switch mechanism according to claim 1, in which said platemember is made of electrically conductive material.

4. A trigger switch mechanism according to claim 1, in which saidrodlike spring is made of electrically conductive material.

5. A trigger switch mechanism according to claim 1, in which saidrockable weight is of generally cylindrical construction and saidcontact member and damping member are in an arcuate shape.

6. A trigger switch mechanism according to claim 5, in which saidcontact member is positioned concentrically with respect to saidrockable weight.

7. A trigger switch mechanism according to claim 1, in which said basemember has a cylindrical recess therein and said coiled spring ismounted in said recess.

8. A trigger switch mechanism according to claim 7, in which anadjustment screw is provided at a bottom of said base member foradjusting the force of compression of said coiled spring.

9. A trigger switch mechanism according to claim 1, in which saiddamping member is made of electrically nonconductive material.

1. A trigger switch mechanism for sensing deceleration of a givenmagnitude resulting from a collision of the motor vehicle to actuatesafety devices mounted thereon, said mechanism comprising: a basemember, a cylindrical member mounted on said base member in an uprightmanner, a plate member mounted atop said cylindrical member, a rodlikespring anchored at its uppermost end to said plate member, anelectrically conductive rockable weight carried by said rodlike springand having a recessed control portion formed in its lower end surface, aball member held in said recessed control portion by a regulated springaction, a coiled spring holding said ball member in said recessedcontrol portion, a contact member provided on the inner wall of saidcylindrical member in front of said rockable weight at a suitable spacetherefrom, and a damping member provided on the inner wall of saidcylindrical member opposite to said contact member for partiallysurrounding said rockable weight thereby serving to absorb the usualshocks and vibrations of said rockable weight developed during operationof the motor vehicle, said rockable weight being forced forwardly cominginto contact with said contact member when said trigger switch mechanismis subjected to said deceleration.
 2. A trigger switch mechanismaccording to claim 1, in which said cylindrical member is made ofelectrically nonconductive material.
 3. A trigger switch mechanismaccording to claim 1, in which said plate member is made of electricallyconductive material.
 4. A trigger switch mechanism according to claim 1,in which said rodlike spring is made of electrically conductivematerial.
 5. A trigger switch mechanism according to claim 1, in whichsaid rockable weight is of generally cylindrical construction and saidcontact member and damping member are in an arcuate shape.
 6. A triggerswitch mechanism according to claim 5, in which said contact member ispositioned concentrically with respect to said rockable weight.
 7. Atrigger switch mechanism according to claim 1, in which said base memberhas a cylindrical recess therein and said coiled spring is mounted insaid recess.
 8. A trigger switch mechanism according to claim 7, inwhich an adjustment screw is provided at a bottom of said base memberfor adjusting the force of compression of said coiled spring.
 9. Atrigger switch mechanism according to claim 1, in which said dampingmember is made of electrically nonconductive material.